Serum biomarkers at disease onset for personalized therapy in multiple sclerosis.

The potential of combining serum neurofilament light chain (sNfL) and glial fibrillary acidic protein (sGFAP) levels to predict disability worsening in multiple sclerosis (MS) remains underexplored. We aimed to investigate whether sNfL and sGFAP values identify distinct subgroups of patients according to the risk of disability worsening and their response to disease-modifying treatments (DMTs). This multicentre study, conducted across thirteen European hospitals, spanned from July 15, 1994, to August 18, 2022, with follow-up until September 26, 2023. We enrolled MS patients who had serum samples collected within 12 months from disease onset and before initiating DMTs. Multivariable regression models were used to estimate the risk of relapse-associated worsening (RAW), progression independent of relapse activity (PIRA), and Expanded Disability Status Scale (EDSS) score of 3. Of the 725 patients included, median age was 34.2 years (IQR, 27.6-42.4), and 509 patients (70.2%) were female. Median follow-up duration was 6.43 years (IQR, 4.65-9.81). Higher sNfL values associated with an elevated risk of RAW (HR of 1.45; 95% CI 1.19-1.76; P < 0.001), PIRA (HR of 1.43; 95% CI 1.13-1.81; P = 0.003), and reaching an EDSS of 3 (HR of 1.55; 95% CI 1.29-1.85; P < 0.001). Moreover, higher sGFAP levels were linked to a higher risk of achieving an EDSS score of 3 (HR of 1.36; 95% CI 1.06-1.74; P = 0.02) and, in patients with low sNfL values, to PIRA (HR of 1.86; 95% CI 1.01-3.45; P = 0.04). We further examined the combined effect of sNfL and sGFAP levels. Patients with low sNfL and sGFAP values (NLGL) exhibited a low risk of all outcomes and served as reference. Untreated patients with high sNfL levels showed a higher risk of RAW, PIRA, and reaching an EDSS of 3. Injectable or oral DMTs reduced the risk of RAW in these patients but failed to mitigate the risk of PIRA and reaching an EDSS of 3. Conversely, high-efficacy DMTs counteracted the heightened risk of these outcomes, except for the risk of PIRA in patients with high sNfL and sGFAP levels. Patients with low sNfL and high sGFAP values (NLGH) showed an increased risk of PIRA and achieving an EDSS of 3, which remained unchanged with either high-efficacy or other DMTs. In conclusion, evaluating sNfL and sGFAP levels at disease onset in MS may identify distinct phenotypes associated with diverse immunological pathways of disability acquisition and therapeutic response.

Soluble CD27 is an intrathecal biomarker of T-cell-mediated lesion activity in multiple sclerosis.

OBJECTIVE: Soluble CD27 is a promising cerebrospinal fluid inflammatory biomarker in multiple sclerosis. In this study, we investigate relevant immune and neuro-pathological features of soluble CD27 in multiple sclerosis. METHODS: Protein levels of soluble CD27 were correlated to inflammatory cell subpopulations and inflammatory cytokines and chemokines detected in cerebrospinal fluid of 137 patients with multiple sclerosis and 47 patients with inflammatory and non-inflammatory neurological disease from three independent cohorts. Production of soluble CD27 was investigated in cell cultures of activated T and B cells and CD27-knockout T cells. In a study including matched cerebrospinal fluid and post-mortem brain tissues of patients with multiple sclerosis and control cases, levels of soluble CD27 were correlated with perivascular and meningeal infiltrates and with neuropathological features. RESULTS: We demonstrate that soluble CD27 favours the differentiation of interferon-γ-producing T cells and is released through a secretory mechanism activated by TCR engagement and regulated by neutral sphingomyelinase. We also show that the levels of soluble CD27 correlate with the representation of inflammatory T cell subsets in the CSF of patients with relapsing-remitting multiple sclerosis and with the magnitude of perivascular and meningeal CD27 + CD4 + and CD8 + T cell infiltrates in post-mortem central nervous system tissue, defining a subgroup of patients with extensive active inflammatory lesions. INTERPRETATION: Our results demonstrate that soluble CD27 is a biomarker of disease activity, potentially informative for personalized treatment and monitoring of treatment outcomes.

Establishing Normal Serum Values of Neurofilament Light Chains and Glial Fibrillary Acidic Protein Considering the Effects of Age and Other Demographic Factors in Healthy Adults.

Multiple studies have shown the importance of blood-based biomarkers indicating axonal damage (serum neurofilament light chains [sNfL]) or astroglia activation (serum glial fibrillary acidic protein [sGFAP]) for monitoring different neurological diseases. However, normal values of these variables remain to be clearly defined, partly due to the influence of different demographic factors. We investigated demographic differences in a cohort of healthy volunteers. A cross-sectional study was conducted including 116 healthy controls with ages between 18 and 69 years (67.5% females; n = 79). sNfL and sGFAP concentrations were measured using single-molecule arrays. Age and body mass index affected sNfL values, and age was found to be the most important factor. The normal values changed with age, and we established normal values for individuals younger than 45 years as <10 pg/mL and for controls older than 45 years as <15 pg/mL. We established normal values at <10 pg/mL for individuals younger than 45 years and <15 pg/mL for older individuals. Alternatively, a Z-score of 1.5 was relevant for all controls. sGFAP was only affected by age. Differences in normal values were evident by 55 years. The highest normality limit for sGFAP was 140 pg/mL for controls under 55 years and 280 for older controls. We defined normal levels for sNfL and sGFAP and their corresponding age-associated changes. These data may contribute to the application of such variables in clinical practice.

Abnormal functional connectivity in radiologically isolated syndrome: A resting-state fMRI study.

BACKGROUND: Radiologically isolated syndrome (RIS) patients might have psychiatric and cognitive deficits, which suggests an involvement of major resting-state functional networks. Notwithstanding, very little is known about the neural networks involved in RIS. OBJECTIVE: To examine functional connectivity differences between RIS and healthy controls using resting-state functional magnetic resonance imaging (fMRI). METHODS: Resting-state fMRI data in 25 RIS patients and 28 healthy controls were analyzed using an independent component analysis; in addition, seed-based correlation analysis was used to obtain more information about specific differences in the functional connectivity of resting-state networks. Participants also underwent neuropsychological testing. RESULTS: RIS patients did not differ from the healthy controls regarding age, sex, and years of education. However, in memory (verbal and visuospatial) and executive functions, RIS patients' cognitive performance was significantly worse than the healthy controls. In addition, fluid intelligence was also affected. Twelve out of 25 (48%) RIS patients failed at least one cognitive test, and six (24.0%) had cognitive impairment. Compared to healthy controls, RIS patients showed higher functional connectivity between the default mode network and the right middle and superior frontal gyri and between the central executive network and the right thalamus (pFDR < 0.05; corrected). In addition, the seed-based correlation analysis revealed that RIS patients presented higher functional connectivity between the posterior cingulate cortex, an important hub in neural networks, and the right precuneus. CONCLUSION: RIS patients had abnormal brain connectivity in major resting-state neural networks and worse performance in neurocognitive tests. This entity should be considered not an "incidental finding" but an exclusively non-motor (neurocognitive) variant of multiple sclerosis.

Peripheral myeloid-derived suppressor cells are good biomarkers of the efficacy of fingolimod in multiple sclerosis.

BACKGROUND: The increasing number of treatments that are now available to manage patients with multiple sclerosis (MS) highlights the need to develop biomarkers that can be used within the framework of individualized medicine. Fingolimod is a disease-modifying treatment that belongs to the sphingosine-1-phosphate receptor modulators. In addition to inhibiting T cell egress from lymph nodes, fingolimod promotes the immunosuppressive activity of myeloid-derived suppressor cells (MDSCs), whose monocytic subset (M-MDSCs) can be used as a biomarker of disease severity, as well as the degree of demyelination and extent of axonal damage in the experimental autoimmune encephalomyelitis (EAE) model of MS. In the present study, we have assessed whether the abundance of circulating M-MDSCs may represent a useful biomarker of fingolimod efficacy in EAE and in the clinical context of MS patients. METHODS: Treatment with vehicle or fingolimod was orally administered to EAE mice for 14 days in an individualized manner, starting the day when each mouse began to develop clinical signs. Peripheral blood from EAE mice was collected previous to treatment and human peripheral blood mononuclear cells (PBMCs) were collected from fingolimod to treat MS patients' peripheral blood. In both cases, M-MDSCs abundance was analyzed by flow cytometry and its relationship with the future clinical affectation of each individual animal or patient was assessed. RESULTS: Fingolimod-treated animals presented a milder EAE course with less demyelination and axonal damage, although a few animals did not respond well to treatment and they invariably had fewer M-MDSCs prior to initiating the treatment. Remarkably, M-MDSC abundance was also found to be an important and specific parameter to distinguish EAE mice prone to better fingolimod efficacy. Finally, in a translational effort, M-MDSCs were quantified in MS patients at baseline and correlated with different clinical parameters after 12 months of fingolimod treatment. M-MDSCs at baseline were highly representative of a good therapeutic response to fingolimod, i.e., patients who met at least two of the criteria used to define non-evidence of disease activity-3 (NEDA-3) 12 months after treatment. CONCLUSION: Our data indicate that M-MDSCs might be a useful predictive biomarker of the response of MS patients to fingolimod.

The Impact of Immunosuppression and Autoimmune Disease on Severe Outcomes in Patients Hospitalized with COVID-19.

Immunosuppression (IS) and autoimmune disease (AD) are prevalent in patients with severe coronavirus disease 2019 (COVID-19), but their impact on its clinical course is unknown. We investigated relationships between IS, AD, and outcomes in patients hospitalized with COVID-19. Data on consecutive admissions for COVID-19 were extracted retrospectively from medical records. Patients were assigned to one of four cohorts, according to whether or not they had an AD (AD and NAD) or were immunosuppressed (IS and NIS). The primary endpoint was development of severe acute respiratory distress syndrome (ARDS); secondary endpoints included death, and a composite of mechanical ventilation (MV) or death. A total of 789 patients were included: 569 (72.1%) male, 76 (9.6%) with an AD, and 63 (8.0%) with IS. Relative to the NIS-NAD cohort, patients in the IS-AD cohort had a significantly reduced risk of severe ARDS (adjusted hazard ratio [aHR] 0.42; 95% confidence interval [CI] 0.23-0.80; p = 0.008). No significant relationships between IS or AD status and either death or the composite of MV and death were identified, although a trend towards higher mortality was identified in the IS-NAD cohort (aHR vs NIS-NAD 1.71; 95% CI 0.94-3.12; p = 0.081). Patients in this cohort also had higher median serum levels of interleukin-6 compared with IS-AD patients (98.2 vs 21.6 pg/mL; p = 0.0328) and NIS-NAD patients (29.1 pg/mL; p = 0.0057). In conclusion, among patients hospitalized with COVID-19, those receiving immunosuppressive treatment for an AD may have a reduced risk of developing severe ARDS.

Non-severe immunosuppression might be associated with a lower risk of moderate-severe acute respiratory distress syndrome in COVID-19: A pilot study.

The role of immunosuppression among coronavirus disease 2019 (COVID-19) patients has not been elucidated and management may be challenging. This observational study included confirmed COVID-19 patients. The primary endpoint was the development of moderate-severe acute respiratory distress syndrome (ARDS). Time to moderate-severe ARDS, the need for mechanical or noninvasive ventilation (MV/NIV), death, and a composite of death or MV/NIV were secondary endpoints. Of 138 patients included, 27 (19.6%) were immunosuppressed (IS) and 95 (68.8%) were male, with a median (IQR) age of 68 (54-78) years. A significantly lower proportion of IS patients (25.9%) compared to non-IS patients (52.3%) developed moderate-severe ARDS, in both unadjusted (0.32; 95% CI, 0.13-0.83; p = .017) and adjusted (aOR, 0.25; 95% CI, 0.08-0.80; p = .019) analyses. After stratifying by pathologies, only IS patients with autoimmune diseases remained significant (aOR 0.25; 95% CI, 0.07-0.98; p = .046). Nonsignificant trends toward a longer time to moderate or severe ARDS, a lower need for MV/NIV, and a lower risk of death or MV/NIV were detected among IS. In our cohort of COVID-19 patients, nonsevere immunosuppression was associated with a lower risk of moderate-severe ARDS, especially among AD. This suggests a potential protective effect from a hypothesized hyper-inflammatory response.

Risk and outcomes of COVID-19 in patients with multiple sclerosis.

BACKGROUND AND PURPOSE: Limited information is available on incidence and outcomes of COVID-19 in patients with multiple sclerosis (MS). This study investigated the risks of SARS-CoV-2 infection and COVID-19-related outcomes in patients with MS, and compared these with the general population. METHODS: A regional registry was created to collect data on incidence, hospitalization rates, intensive care unit admission, and death in patients with MS and COVID-19. National government outcomes and seroprevalence data were used for comparison. The study was conducted at 14 specialist MS treatment centers in Madrid, Spain, between February and May 2020. RESULTS: Two-hundred nineteen patients were included in the registry, 51 of whom were hospitalized with COVID-19. The mean age ± standard deviation was 45.3 ± 12.4 years, and the mean duration of MS was 11.9 ± 8.9 years. The infection incidence rate was lower in patients with MS than the general population (adjusted incidence rate ratio = 0.78, 95% confidence interval [CI] = 0.70-0.80), but hospitalization rates were higher (relative risk = 5.03, 95% CI = 3.76-6.62). Disease severity was generally low, with only one admission to an intensive care unit and five deaths. Males with MS had higher incidence rates and risk of hospitalization than females. No association was found between the use of any disease-modifying treatment and hospitalization risk. CONCLUSIONS: Patients with MS do not appear to have greater risks of SARS-CoV-2 infection or severe COVID-19 outcomes compared with the general population. The decision to start or continue disease-modifying treatment should be based on a careful risk-benefit assessment.

High versus standard doses of corticosteroids in severe COVID-19: a retrospective cohort study.

Despite the increasing evidence of the benefit of corticosteroids for the treatment of moderate-severe coronavirus disease 2019 (COVID-19) patients, no data are available about the potential role of high doses of steroids for these patients. We evaluated the mortality, the risk of need for mechanical ventilation (MV), or death and the risk of developing a severe acute respiratory distress syndrome (ARDS) between high (HD) and standard doses (SD) among patients with a severe COVID-19. All consecutive confirmed COVID-19 patients admitted to a single center were selected, including those treated with steroids and an ARDS. Patients were allocated to the HD (≥ 250 mg/day of methylprednisolone) of corticosteroids or the SD (≤ 1.5 mg/kg/day of methylprednisolone) at discretion of treating physician. Five hundred seventy-three patients were included: 428 (74.7%) men, with a median (IQR) age of 64 (54-73) years. In the HD group, a worse baseline respiratory situation was observed and male gender, older age, and comorbidities were significantly more common. After adjusting by baseline characteristics, HDs were associated with a higher mortality than SD (adjusted OR 2.46, 95% CI 1.59-3.81, p < 0.001) and with an increased risk of needing MV or death (adjusted OR 2.35, p = 0.001). Conversely, the risk of developing a severe ARDS was similar between groups. Interaction analysis showed that HD increased mortality exclusively in elderly patients. Our real-world experience advises against exceeding 1-1.5 mg/kg/day of corticosteroids for severe COVID-19 with an ARDS, especially in older subjects. This reinforces the rationale of modulating rather than suppressing immune responses in these patients.

Optimal response to dimethyl fumarate associates in MS with a shift from an inflammatory to a tolerogenic blood cell profile.

BACKGROUND: The precise mechanism of action of dimethyl fumarate (DMF) treatment in MS remains unknown. OBJECTIVE: To identify the changes in the blood lymphocyte profile of MS patients predicting no evidence of disease activity (NEDA) status after DMF treatment. METHODS: We studied blood lymphocyte subsets of 64 MS patients treated with DMF at baseline and after 6 months of treatment by flow cytometry. NEDA (41 patients) or ongoing disease activity (ODA, 23 patients) were monitored after a year of follow-up. RESULTS: During treatment, all patients experienced an increase in the naive T cells and a decrease in effector memory ones. However, only NEDA patients showed a significant reduction in central memory CD4+ and CD8+ T cells, memory B cells, CD4+ T cells producing interferon (IFN)-gamma, CD8+ T cells producing tumor necrosis factor-alpha (TNF-alpha), and IFN-gamma and B cells producing TNF-alpha. Additionally, they had an increase in regulatory CD56bright cells not observed in ODA group. After treatment, there was a negative correlation between CD56bright cells and CD8+ T cells producing IFN-gamma and TNF-alpha. CONCLUSION: A pro-tolerogenic shift in the blood leukocyte profile associates with an optimal response to DMF in MS.

Lipid-specific immunoglobulin M bands in cerebrospinal fluid are associated with a reduced risk of developing progressive multifocal leukoencephalopathy during treatment with natalizumab.

OBJECTIVE: Progressive multifocal leukoencephalopathy (PML) is a serious side effect associated with natalizumab treatment in multiple sclerosis (MS). PML risk increases in individuals seropositive for anti-John Cunningham virus (JC) antibodies, with prolonged duration of natalizumab treatment, and with prior exposure to immunosuppressants. We explored whether the presence of lipid-specific immunoglobulin M oligoclonal bands in cerebrospinal fluid (CSF; IgM bands), a recognized marker of highly inflammatory MS, may identify individuals better able to counteract the potential immunosuppressive effect of natalizumab and hence be associated with a reduced risk of developing PML. METHODS: We studied 24 MS patients who developed PML and another 343 who did not suffer this opportunistic infection during natalizumab treatment. Patients were recruited at 25 university hospitals. IgM bands were studied by isoelectric focusing and immunodetection. CSF lymphocyte counts were explored in 151 MS patients recruited at Ramon y Cajal Hospital in Madrid, Spain. RESULTS: IgM bands were independently associated with decreased PML risk (odds ratio [OR] = 45.9, 95% confidence interval [CI] = 5.9-339.3, p < 0.0001) in patients treated with natalizumab. They were also associated with significantly higher CSF CD4, CD8, and B-cell numbers. Patients positive for IgM bands and anti-JC antibodies had similar levels of reduced PML risk to those who were anti-JC negative (OR = 1.55, 95% CI = 0.09-25.2, p = 1.0). Higher risk was observed in patients positive for anti-JC antibodies and negative for IgM bands (19% of the total cohort, OR = 59.71, 95% CI = 13.6-262.2). INTERPRETATION: The presence of IgM bands reflects a process that may diminish the risk of PML by counteracting the excess of immunosuppression that may occur during natalizumab therapy.

A two-years real-word study with fingolimod: early predictors of efficacy and an association between EBNA-1 IgG titers and multiple sclerosis progression.

Background: Although fingolimod, a sphingosine 1-phosphate receptor agonist, has shown to be an effective treatment reducing relapse rate and also slowing down the disability progression in relapsing-remitting multiple sclerosis (RRMS) patients, it is important to quickly identify those suboptimal responders. Objective: The main objective was to assess different clinical, radiological, genetic and environmental factors as possible early predictors of response in MS patients treated with fingolimod for 24 months. The secondary objective was to analyze the possible contribution of the environmental factors analyzed to the progression and activity of the disease along the 2-years of follow-up. Methods: A retrospective study with 151 patients diagnosed with MS, under fingolimod treatment for 24 months, with serum samples at initiation and six months later, and with clinical and radiological data at initiation and 24 months later, were included in the study. Clinical and radiological variables were collected to establish NEDA-3 (no evidence of disease activity: patients without relapses, disability progression and new T2 lesions or Gd+ lesions) and EDA (evidence of disease activity: patients with relapses and/or progression and/or new T2 lesions or gadolinium-positive [Gd+] lesions) conditions. Human leukocyte antigen II (HLA-II), EBNA-1 IgG and VCA IgG from Epstein-Barr virus (EBV) and antibody titers against Human herpesvirus 6A/B (HHV-6A/B) were also analyzed. Results: A total of 151 MS patients fulfilled the inclusion criteria: 27.8% was NEDA-3 (37.5% among those previously treated with high efficacy therapies >24 months). The following early predictors were statistically significantly associated with NEDA-3 condition: sex (male; p=0.002), age at baseline (older; p=0.009), relapses 2-years before fingolimod initiation ≤1 (p=0.010), and absence of Gd+ lesions at baseline (p=0.006). Regarding the possible contribution of the environmental factors included in the study to the activity or the progression of the disease, we only found that EBNA-1 IgG titers decreased in 20.0% of PIRA (progression independent from relapse activity) patients vs. 73.3% of RAW (relapse-associated worsening) patients (p=0.006; O.R. = 11.0). Conclusion: MS patients that are male, older, and with a low clinical and radiological activity at fingolimod initiation have a greater probability to reach NEDA-3 condition after two years with this therapy. An intriguing association of EBV with the progression of the disease has also been described, but it should be further study in a larger cohort to confirm these results.

Practical tool to identify Spasticity-Plus Syndrome amongst patients with multiple sclerosis. Algorithm development based on a conjoint analysis.

Introduction: The Spasticity-Plus Syndrome (SPS) in multiple sclerosis (MS) refers to a combination of spasticity and other signs/symptoms such as spasms, cramps, bladder dysfunction, tremor, sleep disorder, pain, and fatigue. The main purpose is to develop a user-friendly tool that could help neurologists to detect SPS in MS patients as soon as possible. Methods: A survey research based on a conjoint analysis approach was used. An orthogonal factorial design was employed to form 12 patient profiles combining, at random, the eight principal SPS signs/symptoms. Expert neurologists evaluated in a survey and a logistic regression model determined the weight of each SPS sign/symptom, classifying profiles as SPS or not. Results: 72 neurologists participated in the survey answering the conjoint exercise. Logistic regression results of the survey showed the relative contribution of each sign/symptom to the classification as SPS. Spasticity was the most influential sign, followed by spasms, tremor, cramps, and bladder dysfunction. The goodness of fit of the model was appropriate (AUC = 0.816). Concordance between the experts' evaluation vs. model estimation showed strong Pearson's (r = 0.936) and Spearman's (r = 0.893) correlation coefficients. The application of the algorithm provides with a probability of showing SPS and the following ranges are proposed to interpret the results: high (> 60%), moderate (30-60%), or low (< 30%) probability of SPS. Discussion: This study offers an algorithmic tool to help healthcare professionals to identify SPS in MS patients. The use of this tool could simplify the management of SPS, reducing side effects related with polypharmacotherapy.

Clinical characteristics and impact on patient-reported outcomes and quality of life of people with ambulatory secondary progressive multiple sclerosis: Discover study.

BACKGROUND: People with secondary progressive multiple sclerosis (pwSPMS) experience increasing disability, which impacts negatively on their health-related quality of life (HRQoL). Our aims were to assess the impact of secondary progressive multiple sclerosis (SPMS) on functional status and HRQoL and describe the clinical profile in this population. METHODS: DISCOVER is an observational, cross-sectional, multicenter study with retrospective data collection in real-world clinical practice in Spain. Sociodemographic and clinical variables, functional and cognitive scales, patient-reported outcomes (PROs), and direct healthcare, and non-healthcare and indirect costs were collected. RESULTS: A total of 297 evaluable pwSPMS with a EDSS score between 3-6.5 participated: 62.3 % were female and 18.9 % had active SPMS. At the study visit, 77 % of them presented an Expanded Disability Scale Score (EDSS) of 6-6.5. Nearly 40 % did not receive any disease-modifying treatment. Regarding the working situation, 61.6 % were inactive due to disability. PROs: 99.3 % showed mobility impairment in EuroQoL-5 Dimensions-5 Levels, and about 60 % reported physical impact on the Multiple Sclerosis Impact Scale-29. Fatigue was present in 76.1 %, and almost 40 % reported anxiety or depression. The Symbol Digit Modalities Test was used to assess cognitive impairment; 80 % of the patients were below the mean score. Participants who presented relapses two years before and had high EDSS scores had a more negative impact on HRQoL. PwSPMS with a negative impact on HRQoL presented a higher cost burden, primarily due to indirect costs. CONCLUSIONS: PwSPMS experience a negative impact on their HRQoL, with a high physical impact, fatigue, cognitive impairment, and a high burden of indirect costs.

Predictive models of multiple sclerosis-related cognitive performance using routine clinical practice predictors.

BACKGROUND: The application of machine learning (ML) to predict cognitive evolution is exceptionally scarce. Computer-based self-administered cognitive tests provide the opportunity to set up large longitudinal datasets to aid in developing ML prediction models of risk for Multiple Sclerosis-related cognitive decline. OBJECTIVE: to analyze to what extent clinically feasible models can be built with standard clinical practice features and subsequently used for reliable prediction of cognitive evolution. METHODS: This prospective longitudinal study includes 1184 people with MS who received a Processing Speed (PS) evaluation at 12 months of follow-up measured by the iPad®-based Processing Speed Test (PST). Six of the most potent classification models built with routine clinical practice features were trained and tested to predict the 12-month patient class label (PST worsening (PSTw) versus PST stable). A rigorous scheme of all the preprocessing steps run to obtain reliable generalization performance is detailed. RESULTS: Based on a 12-month reduction of 10% of the PST raw score, 187/1184 (15.8%) people with MS were classified as PSTw. The trees-based models (random forest and the eXtreme Gradient Boosting) achieved the best performance, with an area under the receiver operating characteristic curve (AUC) of 0.90 and 0.89, respectively. The timing of high-efficacy disease-modifying therapies (heDMTs) was identified as one of the top importance predictors in all the models evaluated. CONCLUSION: Using trees-based machine learning models to predict individual future information processing speed deterioration in MS could become a reality in clinical practice.

Establishing the best combination of the kappa free light chain index and oligoclonal bands for an accurate diagnosis of multiple sclerosis.

Introduction: The immunoglobulin kappa free light chain (KFLC) index has been proposed as a potentially suitable alternative to oligoclonal IgG bands (OCGB) for diagnosing multiple sclerosis (MS), offering automation and reduced processing time. However, there is no consensus on the preferred approach or how to combine both techniques. Methods: This prospective cohort study aimed to determine the best utilization of OCGB and KFLC index in patients with a clinically isolated syndrome (CIS) followed for at least two years. OCGB and KFLC were assessed using isoelectric focusing and immunoblotting and turbidimetry, respectively. Sensitivity, specificity, and accuracy for diagnosing MS were calculated for each method. Results: The study included 371 patients, with 260 (70.1 %) being women, and a median age of 34.9 (27.8 - 43.9) years. Using a cut-off value of 6.1, the KFLC index demonstrated a sensitivity and specificity of 86.3% and 93.9%, respectively. The sensitivity of OCGB (95.3%) was higher (p < 0.001 vs. KFLC index) and the specificity (100%) was comparable to that of the KFLC index (p = 0.5). The concordance between the methods was not uniform across all patients, with 97.8% agreement in patients with KFLC index ≥ 6.1 and 56.0 % in patients with KFLC index < 6.1. In patients with a KFLC index < 6.1, OCGB still identified 75.0 % of MS patients due to its higher sensitivity. An algorithm using the KFLC index as a screening tool and OCGB as an alternative for patients with a negative KFLC index result achieved an accuracy of 96.3 %. Discussion: Combining the KFLC index and OCGB can provide an easily reproducible and accurate method for diagnosing MS, with OCGB primarily reserved for patients with a KFLC index < 6.1.

Molecular signature associated with cladribine treatment in patients with multiple sclerosis.

Introduction: Little is known about the molecular profiling associated with the effect of cladribine in patients with multiple sclerosis (MS). Here, we aimed first to characterize the transcriptomic and proteomic profiles induced by cladribine in blood cells, and second to identify potential treatment response biomarkers to cladribine in patients with MS. Methods: Gene, protein and microRNA (miRNA) expression profiles were determined by microarrays (genes, miRNAs) and mass spectrometry (proteins) in peripheral blood mononuclear cells (PBMCs) from MS patients after in vitro treatment with cladribine in its active and inactive forms. Two bioinformatics approaches to integrate the three obtained datasets were applied: (i) a multiomics discriminant analysis (DIABLO - Data Integration Analysis for Biomarker discovery using Latent variable approaches for Omics studies); and (ii) a multi-stage integration of features selected in differential expression analysis on each dataset and then merged. Selected molecules from the in vitro study were quantified by qPCR ex vivo in PBMCs from MS patients receiving cladribine. Results: PBMCs treated in vitro with cladribine were characterized by a major downregulation of gene, protein, and miRNA expression compared with the untreated cells. An intermediate pattern between the cladribine-treated and untreated conditions was observed in PBMCs treated with cladribine in its inactive form. The differential expression analysis of each dataset led to the identification of four genes and their encoded proteins, and twenty-two miRNAs regulating their expression, that were associated with cladribine treatment. Two of these genes (PPIF and NHLRC2), and three miRNAs (miR-21-5p, miR-30b-5p, and miR-30e-5p) were validated ex vivo in MS patients treated with cladribine. Discussion: By using a combination of omics data and bioinformatics approaches we were able to identify a multiomics molecular profile induced by cladribine in vitro in PBMCs. We also identified a number of biomarkers that were validated ex vivo in PBMCs from patients with MS treated with cladribine that have the potential to become treatment response biomarkers to this drug.

Short- and Long-Term Humoral and Cellular Immune Responses to SARS-CoV-2 Vaccination in Patients with Multiple Sclerosis Treated with Disease-Modifying Therapies.

BACKGROUND: This study aimed to evaluate short- and long-term humoral and T-cell-specific immune responses to SARS-CoV-2 vaccines in patients with multiple sclerosis (MS) treated with different disease-modifying therapies (DMTs). METHODS: Single-center observational longitudinal study including 102 patients with MS who consecutively received vaccination against SARS-CoV-2. Serum samples were collected at baseline and after receiving the second dose of the vaccine. Specific Th1 responses following in vitro stimulation with spike and nucleocapsid peptides were analyzed by quantifying levels of IFN-γ. Serum IgG-type antibodies against the spike region of SARS-CoV-2 were studied by chemiluminescent microparticle immunoassay. RESULTS: Patients undergoing fingolimod and anti-CD20 therapies had a markedly lower humoral response than those treated with other DMTs and untreated patients. Robust antigen-specific T-cell responses were detected in all patients except those treated with fingolimod, who had lower IFN-γ levels than those treated with other DMTs (25.8 pg/mL vs. 868.7 pg/mL, p = 0.011). At mid-term follow-up, a decrease in vaccine-induced anti-SARS-CoV-2 IgG antibodies was observed in all subgroups of patients receiving DMTs, although most patients receiving induction DMTs or natalizumab and non-treated patients remained protected. Cellular immunity was maintained above protective levels in all DMT subgroups except the fingolimod subgroup. CONCLUSIONS: SARS-CoV-2 vaccines induce robust and long-lasting humoral and cell-mediated specific immune responses in most patients with MS.

Blood CD8+ Naïve T-Cells Identify MS Patients with High Probability of Optimal Cellular Response to SARS-CoV-2 Vaccine.

This single-center study included 68 multiple sclerosis (MS) patients who received the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination from one of several approved vaccine preparations in Spain. Blood samples were collected one to three months after the second dose of the vaccine had been administered. Cellular immune responses to the vaccine were assessed using QuantiFERON analysis, and peripheral blood mononuclear cell subsets were assayed using flow cytometry. Response associated with higher percentages of total lymphocytes, naïve CD4+ T-cells (p = 0.028), CD8+ T-cells (p = 0.013), and, mostly, naïve CD8+ T-cells (p = 0.0003). These results were confirmed by analyzing absolute numbers (p = 0.019; p = 0.002, and p = 0.0003, respectively). Naïve CD8 T-cell numbers higher than 17 cells/µL were closely associated with an optimal cellular response to SARS-CoV-2 vaccination (odds ratio: 24.0, confidence interval: 4.8-460.3; p = 0.0001). This finding clearly shows that independent of the treatment received, higher numbers of naïve CD8+ T-cells yield a strong cellular response to SARS-CoV-2 vaccines in MS patients. If this finding is validated with other viruses/vaccines, it could provide a good tool for identifying MS patients undergoing treatment who will develop strong cellular responses to anti-virus vaccines.

Teriflunomide and Epstein-Barr virus in a Spanish multiple sclerosis cohort: in vivo antiviral activity and clinical response.

Background: Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6) have been associated with multiple sclerosis (MS). Teriflunomide is an oral disease-modifying therapy approved for treatment of relapsing forms of MS. In the preclinical Theiler's murine encephalitis virus model of MS, the drug demonstrated an increased rate of viral clearance versus the vehicle placebo. Furthermore, teriflunomide inhibits lytic EBV infection in vitro. Objective: 1. To evaluate the humoral response against EBV and HHV-6 prior to teriflunomide treatment and 6 months later. 2. To correlate the variation in the humoral response against EBV and HHV-6 with the clinical and radiological response after 24 months of treatment with teriflunomide. 3. To analyze the utility of different demographic, clinical, radiological, and environmental data to identify early biomarkers of response to teriflunomide. Methods: A total of 101 MS patients (62 women; mean age: 43.4 years) with one serum prior to teriflunomide onset and another serum sample 6 months later were recruited. A total of 80 had been treated for at least 24 months, 13 had stopped teriflunomide before 24 months, and 8 were currently under teriflunomide therapy but with less than 24 months of follow-up. We analyzed the levels of the viral antibodies titers abovementioned in serum samples with ELISA commercial kits, and the levels of serum neurofilament light chain (Nf-L). Results: Antiviral antibody titers decreased for EBNA-1 IgG (74.3%), VCA IgG (69%), HHV-6 IgG (60.4%), and HHV-6 IgM (73.3%) after 6 months of teriflunomide. VCA IgG titers at baseline correlated with Nf-L levels measured at the same time (r = 0.221; p = 0.028) and 6 months later (r = 0.240; p = 0.017). We found that higher EBNA-1 titers (p = 0.001) and a higher age (p = 0.04) at baseline were associated with NEDA-3 conditions. Thus, 77.8% of patients with EBNA-1 >23.0 AU and >42.8 years (P50 values) were NEDA-3. Conclusion: Treatment with teriflunomide was associated with a reduction of the levels of IgG antibody titers against EBV and HHV-6. Furthermore, higher EBNA-1 IgG titers prior to teriflunomide initiation were associated with a better clinical response.